Fluorescent light socket



Nov, 10, 1953 v N. c. RUSSELL 2,659,058

FLUORESCENT LIGHT SOCKET Filed Feb. 9, 1951 Patented Nov. 10, 1953 FLUORESCENT LIGHT SOCKET Norman C. Russell, Newark, N. J., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application February 9, 1951, Serial No. 210,261

2 Claims.

This invention relates to an electric light fixture and more particularly to a socket for receiving a fluorescent light tube and for preventing the establishment of electrical connections to the terminals on the tube until the tube has been inserted and moved to its proper position.

In fluorescent light fixtures the fluorescent light tube is inserted in the sockets by moving the tube transversely to its length to position the contact pins on the end thereof between spaced contact springs in the sockets and locate the tube on a predetermined axis, after which the tube is rotated through approximately 90 to cause the pins to engage a pair of spring contact members and be locked in notches formed therein. During the application of the tube to the socket, it frequently happens that the tubes instead of being rotated to their final and proper position where they are rmly locked in position in the socket, are only partially rotated into engagement with the spring contact members. Since the tubes will light in this position, there rises a false impression that the tube is in its proper location. It frequently happens that vibrations imparted to the light fixtures loosen the tube and cause it to fall.

It is an object of the present invention to provide a socket for electric lamps for preventing the electrical connection to the terminals of the lamp until the lamp is fully and properly positioned within the socket.

In accordance with one embodiment of the invention as applied to light sockets for receiving fluorescent light tubes, there is provided a receptacle having recesses for receiving the terminal pins on the end of the light tube and guiding them into a predetermined position between a pair of spring contacts in the receptacle and for guiding the tube for rotation to cause the pins to engage the spring contact members to establish an electrical connection therewith. Members of insulating material are mounted on the contact springs in a position to be engaged by the pins during a portion of the arcuate movement of the pins for the purpose of preventing electrical contact between one of the pins and one of the contact springs until the pins and the tube have been rotated sufficiently to locate the pins in their proper position relative to the recesses in the contact springs at which point the pins have moved off of the insulating members and are engaged by the spring contacts to establish an electrical connection therewith and to be yieldably retained in position in the recesses thereof.

Other objects and advantages will become apparent by reference to the following detailed description thereof and the accompanying drawings illustrating one embodiment of the invention, in which Fig. l is a side elevational view of a fluorescent light tube mounted in a pair of light sockets embodying the present invention;

Fig. 2 is an enlarged side elevational view of one of the light sockets showing the tube in position therein and with parts in section;

Fig. 3 is a front elevational View of thesocket indicated as taken on the line 3-3 of Fig. 2;

Figs. 4 and 5 are fragmentary elevational views of the sockets showing the contact springs therein and the terminal pins of the light tube in changed positions; and

Fig. 6 is a detailed sectional view showing the insulating member mounted on the contact spring.

The present invention is shown embodied in sockets for use with fluorescent light tubes, but it will be understood that the sockets may be used with any light bulb having a pair of terminal pins projecting from one end thereof. The fluorescent light tube it has a pair of spaced, diametrically opposed pins 52 projecting therefrom at each end thereof which pins are received in a pair of sockets It for supporting the tube. The sockets it may be mounted on or supported by a suitable supporting member in any well known manner. As shown in Figs. 2 to 5 of the drawings, the socket comprises a hollow body member It of insulating material having a fiat back wall I! and a marginal wall [8 extending transversely therefrom around the side and bottom portions thereof. Also extending from the rear wall in spaced relation to the wall it is a cylindrical projection or post 28. The post 20 and the lower portion of the wall It are vertical slots 2! and 22 for providing clearance for the terminal pins l2 and for guiding them for vertical movement relative to the socket. A cover plate 24 of insulating material is secured to the socket within the marginal walls is and in spaced relation to the rear wall ll. At its lower end, the cover plate 24 is provided with a circular aperture 25 in concentric relation to the circular post 26) to form a circular slot about the post, and with a slot 26 in alignment with the slot 22. The slots 22, 26 and 2| form a guide for receiving and guiding the terminal pins 12 of the fluorescent tube vertically, and the cover plate 24 serves to stop the pins l2 and locate the tube It in a predetermined position with the axis thereof in alignment with the axis of the post 20 and to guide the pins l2 for rotary movement about the axis of the post.

provided with aligned A pair of contact springs 30 are enclosed within the socket in spaced relation to each other and secured at their upper ends to a portion of the socket member by screws 32 which are electrically connected to a circuit for supplying current to the contact springs. Near the lower end thereof, the contact springs 30 are formed with obliquely disposed portions or arms 34 and 35 to provide V-shapednotches and the lower ends. 36 of the springs 30 are outwardly curved as indicated in Figs. 4 and 5. sides of the circular post 20 and biased inwardly toward each other, the apex of the \'I--shaped notched portions of the contactsprings 30 form seats which are adapted to engage. the. pins 1-2 of the fluorescent tube when the tube. is improper position in the socket to establish an electrical connection with the pins to supplycurrentto the tube, and to yieldably lock the pins 12 and; the tube It! in assembled position in the sockets. The socket structure thus far described. is conventional, and the application of the tube to the socket follows the regular procedure in which the pins l2 are aligned with the grooves 22 and 2'1, and moved vertically to a first position shown in Fig. 3, after which the tube is rotated 90 to move the pins into engagement with the apexes of the notches of the contact springs 30.

In order to prevent contact between both of the terminal pins 12 of the tube in and the spring contacts 36, except when the pins have been moved to their final position shown in Fig 5, where they are yieldably locked the sockets IS, a pair of insulating members 31 in the form of fiat rectangular buttons are mounted on the upper inclined portions 34 of the springs 30; Rectangular apertures 38 are formed in the portion 34 of the springs, and the insulating members 31' having grooves in the ends thereof are pressed into the apertures and retained therein. The insulating members 31 are so positioned as to be engaged by one of the pins TZ during the greater portion of the turning movementof the-pins from their first position shown in Fig. 3 to theirfinal position shown in Fig. 5, and to disengage the pins 12 and permit the springs 25' to engage both of the pins and establish electricalcontact therewith when the pins reach' their" proper position shown in Fig. 5. Thus in an intermedi'ateposh tion as indicated in Fig. 4, one of the pair of insulating buttons 31 is in engagement with one of thepins l2 and serves to separate the contact spring from the pin l2, and thereby prevent completion of the circuit to thetube lfl'; ItwilI' thus be seen that with the insulating members 31 on the springs St, the tube will not light if it is-in sertedin the sockets and only partially rotated to an intermediate position, and thatitishecessary that the tube be rotated to its final and proper position in order to establish electrical contact between the springs 31'! and the pins 12 and cause the tube to light, and that in this position the pins I2 and the tube are yieldably-retained against movement tending to removethem from the socket.

Although the insulating means 31' are shown as flat members attached tothe portions 34" of each of the springs 30, it will be understood that they may be otherwise arranged and if desired positioned on the portions 35- of thesprings 30; or both of the insulating members 31 mounted" on a single spring to accomplish the same purpose.

It is to be understood that the above-described arrangements are simply illustrative of the application of the principles of this invention. Nu"- Disposed on opposite.

merous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

1. A connector socket for an electric lamp having a pair of terminal pins extending from one end thereof in spaced, andv parallel relation to each other comp-rising a hollow base member of insulating material having an opening in one face thereof and having a cylindrical post extending into said opening to form an annular slot surrounding the post in concentric relation thereto.,, saidsone faceof the hollow member having a. slot intersecting said annular slot and extending from one edge of the member and diametrically through said post for guiding the pair of pins onsaid lamp for movement in one direction into the socket to a position with the pins on opposite sides of the post, whereby the lamp may be rotated and the pins revolved about the post to anoperative position, a pair of metal contact springs mounted in the hollow, base member, each of said springs having a pair of obliquely disposed arm portions forming a V-shaped notch, said springs being arranged with the V-shaped notches on opposite sides of the post and the slot therethrough and stressed for movement into, close proximity to said post and. in the path of movement of the terminal pins and with the apexes of the. notches disposed diametrically opposite each other. and forming seats in the springs adapted to engage the. terminal pins in response to. the revolution of the terminal pins to said operative position, and to yieldably hold the pins against turning movement, a plurality of the arms of said contact springs having apertures formed therein. adjacent to. the apexes of said V-shaped notches, and. insulating memberssecured to said arms in the apertures thereof and engageable with the terminal pins as the lamp is rotated for insulating one of the pins from. the contact spring fora predetermined portion of the arouate movement of the pin; said insulating memhers being spaced from the apexm of said V- shaped notches and the seats in the springs a distance sufficient to allow the pins to move into contactwith the seats and establish an electrical connection with the contact springs when the pins have been rotated into operative position in alignment with the. seats of the contact springs.

2. A connector socket for an electric lamp having a pair of terminal pins extending from one end thereof in spaced and parallel relation toeach other comprising a hollow base member ofinsulating material having an opening in one face thereof and having a cylindrical post extending into said opening to form an annular slot surrounding the post, said one face of the hollow member having a slot intersecting said annular slot and extending from one edge of the member and diametrically through said post for guiding the pair of pins on said lamp for movement in one direction into the socket to a position with the pins on opposite sides of the post, whereby the lamp may be rotated and the pins revolved about the post to an operative position, a pair of metal contact springs mounted in the hollow base member, each of said springs having a pair of obliquely disposed arm portions forming a V-shaped notch, said springs being arranged with the V-shaped notches on opposite sides of the post and the slot therethrough and stressed for movement into close proximitytosaid post and in the path of movement of the terminal pins and with the apexes of the notches disposed diametrically opposite each other and forming seats in the springs adapted to engage the terminal pins in response to the revolution of the terminal pins to said operative position and to yieldably hold the pins against turning movement, a pair of the arms of said contact springs having apertures formed therein adjacent to the apexes of said V-shaped notches, and insulating members having grooved 10 edge portions secured to said arms in the apertures thereof and 'engageable with the terminal pins as the lamp is rotated for insulating one of the pins from the contact spring for a predetermined portion of the arcuate movement of the pin, said insulating members being spaced from the apexes of said V-shaped notches and the seats in the springs a distance suificient to 6 allow the pins to move into contact with the seats and establish an electrical connection with the contact springs when the pins have been ro tated into operative position in alignment with the seats of the contact springs.

NORMAN C. RUSSELL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,555,524 Wold June 5, 1951 FOREIGN PATENTS Number Country Date 572,479 England Oct. 10, 1945 629,756 England Sept. 27, 1949 

